Jennifer Wright, upon Googling, it says that it closes at 6pm. I didn't further investigate the cost. In addition to the per person charge to swim, I know there is a $5 state park parking fee for each car. vans with 15 passengers cost more. You may gain most information from calling Franklin D Roosevelt State park
It is open but not sure what the closing time is and no idea what cost is sorry I can not be more help
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